1. Field of the Invention
The present invention relates to monoclonal antibodies capable of reacting with cancer cells from more than one human organ but substantially not reacting with normal cells, a process for production of the monoclonal antibodies, hybridoma cell lines producing the monoclonal antibodies, and a process for production of the cell lines.
2. Description of the Related Art
Since the technique for cell fusion was published (Nature, 256, 495-497, 1975), various kinds of monoclonal antibodies have been prepared and studied for application in the diagnosis and therapy of diseases such as cancer. (See, GANN, 75, 485, 1983; Proc. Natl. Acad. Sci. USA, 75, 3405, 1978; Proc. Natl. Acad. Sci. USA, 76, 1438, 1979; and Science, 212, 53 (1981), etc.)
To use a monoclonal antibody for the diagnosis of cancer, the monoclonal antibody must react with or bind to the cancer cells but should not react with or bind to normal cells. In some cases, it is desirable that the monoclonal antibody react with or bind to cancer cells from more than one human organ, so that more than one kind of cancer cell can be simultaneously detected.
However, known monoclonal antibodies against human cancer are substantially reactive with human normal cells. Therefore, there are problems with the prior art monoclonal antibodies when practically used for the diagnosis of cancer.
Japanese Unexamined Patent Publication No. 59-128397 discloses a monoclonal antibody against human stomach cancer, which reacts with well-differentiated stomach cancer cells but which has only a weak reaction with poorly-differentiated stomach cancer cells. This publication does not disclose whether the monoclonal antibody reacts with normal cells.
Therefore, it is strongly desired to provide monoclonal antibodies capable of reacting with cancer cells from more than one human organ but substantially not reacting with normal cells.